TERTIARY FORMATIONS. 177

Pelecypods and Gastropods are the common molluscan forms, and speci-
mens of these are found in almost every exposure. The gigantic Ostrea
georgiana that occurs in such abundance at Polloksville and near Oli-
vers is one of the most interesting forms of this formation. It seems,
however, to have had a very local distribution, so cannot be used to any
great extent for purposes of correlation.

The most striking characteristics of the Trent fauna are the great
quantities of bryozoan remains. Almost every outcrop of the formation
will furnish specimens of this group, while in some places scarcely any
other fossils occur. Spines and occasional tests of Hchinoids are also
common and are associated with the remains of the Bryozoa. Dr. M.
W. Twitchell has determined the following species of Echinoids from
the Eocene of Craven County:

Scutella alta Conrad.
Echinocyamus parvus Emmons.
Cidaris carolinensis Emmons.
Cidaris mitchelli Emmons.

He believes the fossils indicate the upper Claibornian age of the
strata.

Thus far very little work has been done on the Trent fauna, but in
the near future it is planned to make a detailed study of these interesting
forms. ;

With the exception of a few outliers along Contentnea Creek and
in Harnett and Moore counties, outcrops of the Trent formation are
confined to the area lying between the Neuse and Cape Fear rivers and
extending from New Bern westward to Raleigh. In Jones County it
attains its greatest development. It outcrops as continuous strata for
many miles along the Trent River and its tributaries, and apparently
underlies the entire western part of the county, though concealed from
view except in the stream valleys. In Craven County it outcrops in
several places along the Neuse River west of New Bern and along the
Trent River between New Bern and Polloksville. It probably underlies
the greater part of that portion of the country lying south of the Neuse
River and west of New Bern. In Pitt and Greene counties it is reported
to occur along Contentnea Creek in the vicinity of Snow Hill. In
Lenoir County it outcrops along the Neuse River a few miles below
Kinston, and it is believed to underlie the Miocene and Pleistocene of
the southern part of the county, though no exposures are known. It is
exposed in several places along the New River in and near Jacksonville.

In Wayne County the Trent formation is discontinuous, but outerops
in several places. In the Sarpony Hills, on the south side of the Neuse

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